Your comparison logic is flawed.
First, you can't compare that both use steering wheels, have engines etc..thats like saying both phones have a display, processor, etc. Parts arent the issue here.
It's the look of the device and interface. That is equivalent to the 'design/look' of a vehicle.
Can you cover up a Ford logo on a F-150 and cover up the Chevy logo on a Silverado and tell the difference between trucks in design from a glance. I can. Grill, lights, body styling, etc
Can you cover up the logo on a BMW3 and Audi A4 and tell the difference even though both are sedans from a glance? I can. Grill, lights, body styling, etc.
That IS what a design difference is and what Apple is talking about.
[snip]
Apple is making a point like this. You can't tell from a 'glance' that the Samsung Galaxy isn't an iPhone.
Each of these companies have a 'distinct' set of styling elements that make them 'theirs'...grills, lights, etc.
Proving the point.
http://www.loopinsight.com/2012/08/...to-stop-samsung-and-google-from-copying-them/